The present invention relates to a process cartridge and an electrophotographic image forming apparatus to which the process cartridge is detachably mountable.
Here, the electrophotographic image forming apparatus forms an image on a recording material through an electrophotographic image-formation-type process. Examples of electrophotographic image forming apparatus include an electrophotographic copying machine, an electrophotographic printer (laser beam printer, LED printer or the like), a facsimile machine and a word processor.
The above-described process cartridge contains as a unit an electrophotographic photosensitive member and a charging means, a developing means or a cleaning means in the form of a cartridge that is detachably mountable to a main assembly of an image forming apparatus. The process cartridge may contain an electrophotographic photosensitive member and at least one of a charging means, a developing means and a cleaning means in the form of a cartridge that is detachably mountably to a main assembly of an image forming apparatus. The process cartridge may contain an electrophotographic photosensitive member and at least developing means in the form of a cartridge that is detachably mountably to a main assembly of an image forming apparatus.
With a process-cartridge type apparatus, the servicing or maintenance operations can be in effect carried out by users, so that the operativity is significantly improved, and therefore, the process-cartridge type apparatus is widely used in the electrophotographic field.
With the increasing demand for a longer service life of the process cartridge, the amount of the developer accommodated in the process cartridge increases, and the size of the process cartridge also increases. Correspondingly, the operativity of the process cartridge is influenced. Additionally, the positioning of the process cartridge relative to the main assembly may be influenced by an increase in the weight of the cartridge.
Accordingly, it is a principal object of the present invention to provide an improved process cartridge and an electrophotographic image forming apparatus in which the process cartridge is mounted and demounted relative to a main assembly of the image forming apparatus.
It is another object of the present invention to provide a process cartridge and an electrophotographic image forming apparatus in which the positional accuracy of the process cartridge relative to the image forming apparatus is improved.
According to an aspect of the present invention, there is provided a process cartridge detachably mountably to a main assembly of an electrophotographic image forming apparatus, comprising: an electrophotographic photosensitive member; a developing member for developing an electrostatic latent image formed on the electrophotographic photosensitive member; a developer accommodating portion for accommodating a developer to be used by the developing member to develop the electrostatic latent image; a cartridge guide being guided by a main-assembly-side guide provided in the main assembly of the apparatus; a first cartridge positioning portion, provided at one end portion in an axial direction of the electrophotographic photosensitive member, for engagement with a first main-assembly-side positioning portion, provided in the main assembly of the apparatus, in response to falling of a side of the process cartridge opposite from a side having the developer accommodating portion in a direction crossing with the axial direction of the electrophotographic photosensitive member by operation of a lever provided in the main assembly of the apparatus; a second cartridge positioning portion, provided at the other end portion in an axial direction of the electrophotographic photosensitive member, for engagement with a second main-assembly-side positioning portion, provided in the main assembly of the apparatus, in response to falling of a side of the process cartridge opposite from a side having the developer accommodating portion in a direction crossing with the axial direction of the electrophotographic photosensitive member by operation of a lever provided in the main assembly of the apparatus.
These and other objects, features and advantages of the present invention will become more apparent upon a consideration of the following description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.